Display panel, pixel driving circuit, and drving method thereof

Abstract

The present application provides a pixel driving circuit, which comprises a driving transistor, which comprises a gate terminal, a source terminal, and a drain terminal. The source terminal is respectively connected with a driving-voltage-signal terminal and a charge-voltage terminal via a first switch and a second switch. The charge-voltage terminal is connected with a data-voltage-signal terminal via a third switch. The gate terminal is connected with an initial-voltage-signal terminal via a fourth switch, and the gate terminal is connected with the drain terminal via a fifth switch. A first capacitor is connected with the gate terminal and the charge-voltage terminal, a second capacitor is connected with the gate terminal and a ground terminal. The present application further provides a pixel driving method and a display panel.

What is claimed is: 
     
       1. A pixel driving circuit, comprising a driving transistor, a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a first capacitor, a second capacitor, a charge-voltage terminal, an initial-voltage-signal terminal, a data-voltage-signal terminal, and a driving-voltage-signal terminal; wherein the driving transistor comprises a gate terminal, a source terminal, and a drain terminal;
 the source terminal is respectively connected with the driving-voltage-signal terminal and the charge-voltage terminal via the first switch and the second switch, the charge-voltage terminal is connected with the data-voltage-signal terminal via the third switch; the gate terminal is connected with the initial-voltage-signal terminal via the fourth switch, and the gate terminal is connected with the drain terminal via the fifth switch; 
 the first capacitor is connected with the gate terminal and the charge-voltage terminal, the second capacitor is connected with the gate terminal and a ground terminal. 
 
     
     
       2. The pixel driving circuit according to  claim 1 , further comprising a first control-signal terminal and a second control-signal terminal, wherein the first control-signal terminal and second control-signal terminal are respectively connected with a control terminal of the first switch and a control terminal of the second switch, so as to control on/off of the first switch and the second switch. 
     
     
       3. The pixel driving circuit according to  claim 2 , further comprising a third control-signal terminal and a fourth control-signal terminal, wherein the third control-signal terminal and the fourth control-signal terminal are respectively connected with a control terminal of the third switch and a control terminal of the fourth switch, so as to control on/off of the third switch and the fourth switch. 
     
     
       4. The pixel driving circuit according to  claim 3 , further comprising a fifth control-signal terminal, wherein the fifth control-signal terminal is connected with a control terminal of the fifth switch, so as to control on/off of the fifth switch. 
     
     
       5. The pixel driving circuit according to  claim 4 , further comprising a sixth switch, a light-emitting diode and a negative voltage-signal terminal; wherein the first control-signal terminal is connected with a control terminal of the sixth switch to control on/off of the sixth switch; the light-emitting diode comprises a positive terminal and a negative terminal, the sixth switch is connected between the drain terminal and the positive terminal to control on/off of the driving transistor and the light-emitting diode, the negative terminal is connected with the negative voltage-signal terminal. 
     
     
       6. A display panel, comprising a pixel driving circuit, wherein the pixel driving circuit comprises a driving transistor, a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a first capacitor, a second capacitor, a charge-voltage terminal, an initial-voltage-signal terminal, a data-voltage-signal terminal, and a driving-voltage-signal terminal; wherein the driving transistor comprises a gate terminal, a source terminal, and a drain terminal;
 the source terminal is respectively connected with the driving-voltage-signal terminal and the charge-voltage terminal via the first switch and the second switch, the charge-voltage terminal is connected with the data-voltage-signal terminal via the third switch; the gate terminal is connected with the initial-voltage-signal terminal via the fourth switch, and the gate terminal is connected with the drain terminal via the fifth switch; 
 the first capacitor is connected with the gate terminal and the charge-voltage terminal, the second capacitor is connected with the gate terminal and a ground terminal. 
 
     
     
       7. The display panel according to  claim 6 , further comprising a first control-signal terminal and a second control-signal terminal, wherein the first control-signal terminal and second control-signal terminal are respectively connected with a control terminal of the first switch and a control terminal of the second switch, so as to control on/off of the first switch and the second switch. 
     
     
       8. The display panel according to  claim 7 , further comprising a third control-signal terminal and a fourth control-signal terminal, wherein the third control-signal terminal and the fourth control-signal terminal are respectively connected with a control terminal of the third switch and a control terminal of the fourth switch, so as to control on/off of the third switch and the fourth switch. 
     
     
       9. The display panel according to  claim 8 , further comprising a fifth control-signal terminal, wherein the fifth control-signal terminal is connected with a control terminal of the fifth switch, so as to control on/off of the fifth switch. 
     
     
       10. The display panel according to  claim 9 , further comprising a sixth switch, a light-emitting diode and a negative voltage-signal terminal; wherein the first control-signal terminal is connected with a control terminal of the sixth switch to control on/off of the sixth switch; the light-emitting diode comprises a positive terminal and a negative terminal, the sixth switch is connected between the drain terminal and the positive terminal to control on/off of the driving transistor and the light-emitting diode, the negative terminal is connected with the negative voltage-signal terminal. 
     
     
       11. A pixel driving method, comprising:
 providing a pixel driving circuit, which comprises a driving transistor, a first capacitor, a second capacitor, and a charge-voltage terminal; the driving transistor comprises a gate terminal, a source terminal and a drain terminal; the first capacitor is connected with the gate terminal and the charging voltage terminal; the second capacitor is connected with the gate terminal and the ground terminal; 
 a reset phase, loading an initial voltage at the gate terminal and loading a data voltage at the charge-voltage terminal, so as to reset a potential of the charge-voltage terminal and a potential of the gate terminal; 
 a storage phase, loading the data voltage at the charge-voltage terminal, turning on the charge-voltage terminal and the source terminal, and turning on the gate terminal and the drain terminal, so that the gate terminal is charged by the data voltage until a potential difference between the source terminal and the gate terminal is Vth, the Vth is the threshold voltage of the driving transistor, and the Vth is stored in the first capacitor, and a potential of the gate terminal is stored in the second capacitor; 
 a lighting phase, loading a driving voltage at the source terminal and the charge-voltage terminal, so as to change the potential of the gate terminal to stabilize the driving current of the driving transistor. 
 
     
     
       12. The pixel driving method according to  claim 11 , wherein the pixel driving circuit further comprises a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a light-emitting diode, a first control-signal terminal, a second control-signal terminal, a third control-signal terminal, a fourth control-signal terminal, a fifth control-signal terminal, an initial-voltage-signal terminal, a data-voltage-signal terminal, and a driving-voltage-signal terminal; the source terminal is respectively connected with the driving-voltage-signal terminal and the charge-voltage terminal via the first switch and the second switch, the charge-voltage terminal is connected with the data-voltage-signal terminal via the third switch; the gate terminal is connected with the initial-voltage-signal terminal via the fourth switch, the gate terminal is connected with the drain terminal via the fifth switch; the sixth switch is connected between the drain terminal and the light-emitting diode; the first control-signal terminal is connected with a control terminal of the first switch and a control terminal of the sixth switch, the second control-signal terminal is connected with a control terminal of the second switch; the third control-signal terminal and the fourth control-signal terminal are respectively connected with a control terminal of the third switch and a control terminal of the fourth switch; the fifth control-signal terminal is connected with a control terminal of the fifth switch;
 in the reset phase, loading the third control-signal terminal and the fourth control-signal terminal with a low-level signal, loading the first control-signal terminal, the second control-signal terminal, and the fifth control-signal terminal with a high-level signal, to turn on the third switch and the fourth switch, and turn off the first switch, the second switch, the fifth switch, and the sixth switch, loading the charge-voltage terminal with the data voltage via the third switch, the data voltage is Vdata, loading the gate terminal with the initial voltage via the fourth switch. 
 
     
     
       13. The pixel driving method according to  claim 12 , wherein in the storage phase, loading the second control-signal terminal, the third control-signal terminal and the fifth control-signal terminal with a low-level signal, loading the fourth control-signal terminal and the first control-signal terminal with a high-level signal, to turn on the second switch, the third switch, and the fifth switch, and turn off the first switch, the fourth switch, and the sixth switch turn off, loading the source terminal with the data voltage via the second switch and the third switch, and charging the gate terminal with the data voltage via data voltage the third switch, the second switch, the driving transistor, and the fifth switch, until a potential of the gate terminal is Vdata−Vth. 
     
     
       14. The pixel driving method according to  claim 13 , wherein the pixel driving circuit further comprises a negative voltage-signal terminal, the light-emitting diode comprises a positive terminal and a negative terminal, the sixth switch is connected between the drain terminal and the positive terminal, and the negative terminal is connected with the negative voltage-signal terminal;
 in the lighting phase, loading the third control-signal terminal, the fifth control-signal terminal and the fourth control-signal terminal with a high-level signal, loading the first control-signal terminal and the second control-signal terminal with a low-level signal, so as to turn on the third switch, the first switch, and the sixth switch, and turn off the second switch, the fifth switch, and the fourth switch are turned off; loading the source terminal with the driving voltage via the first switch, the driving voltage is Vdd, charging the charge-voltage terminal with the driving voltage charges via the first switch and the third switch, the potential of the gate terminal is Vdata−Vth+δV, and the potential difference between the source terminal and the gate terminal is Vdd−Vdata+Vth−δV, and δV=Vdd−Vdata*C 1 /C 1 +C 2 ), C 1  is a capacitance value of the first capacitor, C 2  is a capacitance value of the second capacitor, so that the driving current is independent of the threshold voltage; and the first switch, the driving transistor and the sixth switch are turned on, so that the driving-voltage-signal terminal and the negative voltage-signal terminal are turned on, for driving the light-emitting diode light by the driving current.